Electrical energy is transmitted using power lines. Power lines include electrical conductors configured to conduct the electrical energy. The electrical conductor may be wound onto a cable reel in order to be sold or transported. Determining how long a conductor is, especially when it is on a cable reel, is difficult. This problem may be complicated when a portion of the cable on the reel is cut off and used, thus leaving an unknown amount of the cable on the reel. Also, since the cable may be sold by length, knowing the length of a cable on a reel can help determine cost for the reel of cable.